markocosic

Careful cooling through ducts if they're not known to be insulated well. Condensation and mould/rot may ensue. A ducted unit will need a return air plenum to operate - I assume that you've though this through but can we sanity check? I assume that heating a single hall and leaving doors open is out of the question?

Ouch. "3 kW" with a C16 breaker in most apartments. Kettle and oven ok. Kettle and washing machine or dishwasher ok. You get used to using one white good at a time though; and "auto resumes after power failure" is a feature that the shops highlight on white goods! 7 kW to allow induction hobs is spendy to retrofit unless the entire staircase does it at the same time.

Not of the sort required. They rely on the mechanical valves for full flow system balancing (the thing that heat pumps require/Mike wanted to automate) The actuator head has control over room temperature but doesn't regulate the max flow rate. (i.e. you still need the lockshield or presettable trv body to be setup before the temperature controlling head is added)

The players active in the space (Danfoss etc) concluded that the market for a mains powered TRV that could take the place of properly commissioned mechanical valves would be vanishingly small.

Noise noise noise noise noise noise And visual amenity Boilers are indoors hence fewer restrictions. Heat pumps can also be indoors. For example: https://www.qvantum.com/ISH23/ The non-retail utility companies (i.e. not the Ovo/Octopus sort but the ones who are interested in hard buried assets) are trying to work out how to offer communal ground arrays. Pay £200 a year for a low grade heat source at your boundary. It could be some buried plastic pipe full of an antifreeze mix that sucks heat from the ground. It could have other heat dumped into it; doesn't matter to you sir. Then chuck a small box under the sink that upgrades this to 70C supply temperature; and a box on the wall that stores enough hot water to be useful; and away you go. To me that's far more appealing. No noisy bulky junk in the garden waiting for the gypsies to steal it. No practical flow temperature limitations. No complex design between your heat pump and the heat source. Just pay the service fee as you do for cold water and excrement in the other direction. Scalable if you can persuade a sufficient number on the same street to switch. Installed alongside upgraded electricity supplies for EV charging etc. (as these are what will melt the LV system not heat pumps)

It's been proposed and attempted but is not viable on battery power.

I view that as "not expressly lawful" rather than "expressly unlawful" Else yes. It's something lots of people want right now. Prices are therefore high because there are currently plenty of folks for whom throwing money at the problem (a) is practical vs the number of suppliers. The "industry" is not a homogenous blob. The installers are indeed very happy with the current situation. The manufacturers and energy companies would prefer greater volumes. They make their money on the boxes and the subsequent energy supplies not the installs. They'll be the ones encouraging additional installers BUT they'll not be independent installers sufficiently skilled / free to do any old job but rather only just good enough to install their manufacturer / energy company supplied kit.

It's currently setup TN-C-S with bonding to the borehole pump and one of the legs of the house. I'm wondering if neutral currents flowing through the borehole pump and the founds are a good idea though. In answer to capacity yes. I asked for: 22 kW (32A) 3-phase to the boundary, 32A 3-phase cable laid across the plot to where the access road / parking spot for an EV would be; then 32A 3-phase cable laid to the house location from there; but only a single phase 32A 7kW supply to be made for now because you pay for connected capacity and as yet we no EV and I haven't won the argument with SWMBO about where to put 22 kW of PV... Instead I got: "7 kW" 3-phase cable laid only to the house using a long piece of aluminium string that's not far off the price of twin and earth in copper. https://online.depo-diy.lt/product/34510 It's actually 10 kW given that it's a C13 breaker that trips at 1.13x13A protecting it but that's only if you can load the phases equally. Can't complain too much. What the wife lost in translation between myself and the contractor working for the electricity board she won by allowing the contractor to be sexist pigs expecting any old excuse for being late to stick. 50-50 split between electricity board and ourselves for connection cost and €X per day late she notes. Duly sets diary date for the point late fees would exceed contract value. Makes an offer to agree that the connection works were complete on the date that late fees would mean the contract was still worth 100% of the original value conditional on a goodwill gesture of their eating our 50%. Could fix it with a supply upgrade and a cable upgrade. (shouldn't melt at 32A / 22 kW but I think voltage drop is a touch much over the length involved) Too mean to pay the €3 per kW per month capacity fee for 22 kW. Heat pump. Induction hob. Oven. Borehole pump. Quooker. White goods. It'll be a test of circuit assignment and diversity in practice!

It's not simple to be a "recognised compliance scheme" (for grant funding eligibility purposes) but it's simple to word for word copy the noise requirement for planning purposes.

Yet nothing to stop him rendering it afterwards under PD?

Exactly this. With direct technical equivalence they wouldn't have a leg to stand on should any enforcement action be attempted with regards noise.

Should I use TT or TN-C-S earthing? Rural site with "7 kW" 3-phase supply. 4-core supply (3 phases and neutral) with the neutral notionally at earth potential. Yes that's 7 kW split over three phases and not a typo. There's a borehole for water. It is probably the most locally earthed thing on the build. There are 50+ groundscrews into damp sand/clay as the foundations. These are also very well earthed. Consumer unit is all RCBO. (Hager 30 mA Type A) The transformer is small and/or the incoming cable is a long piece of wet string. Flip a kettle on and you'll drop from 233 VAC to 229 VAC from phase>neutral. You notice the lights dim slightly. If the kettle is on a different phase you'll notice the lights brighten up slightly. The neutral is moving. Should I use the imported TN-C-S earth or TT this? If TN-C-S Borehole pump should be earthed. For safety (although the supply pipe is plastic), for EMC (inverter driven), and for lightning (try divert nasties to earth before they hit the motor windings) If I connect the incoming neutral to the earth used by the borehole pump this is going to result in currents flowing to earth via the pump as the neutral moves. Motor probably won't like that. If I were also to tie it to the groundscrews to reduce currents in the borehole pump/provide some redundancy against cable damage it will result in currents flowing to earth via the screws. The galv probably won't like that either. Am I being daft in thinking that a TT earthing arrangement might be more appropriate here? Use the borehole pump AND the groundscrews as the earth reference for the house. Allow the incoming neutral to float about as it pleases whilst supplying the loads. Pop some SPDs between incoming phases and neutral. This will be downstream of the main incoming MCB (they fit a 13A Type C after the meter, for power limiting purposes, that's not ours to touch) and hopefully sends anything nasty on the incoming line back to the transformer whilst also dropping the connection to the house; which shouldn't be an attractive earth because that neutral line isn't connected to the borehole pump casing etc as it would be if the installation were made TN-C-S.

Nothing whatsoever. Why don't they want do? Risk of audit etc. So they setup, get ticketed using something like https://www.easy-mcs.com/, do a bunch of work, then crash and burn and phoenix from the ashes again.

Industry is not homogeneous. MCS is government. The government promoted MCS so that they could claim that there's a compliance scheme and that all heat from heat pumps could be considered renewable in the eyes of the EU. MCS only has teeth because the government allow it. The moment it isn't the government endorsed union it dies on its feet. Industry hates it. Only MCS likes MCS. Or MCS.and Octopus et al who are large enough for the overhead to be small and value it keeping competition out. They're not the industry though.

Not with range limited TRVs. It would be obvious that the range was limited and management would have to grow enough of a spine that they're prepared to have that conflict. If you have tha authority to limit choice you surely also have the authority to call folks out on being ridiculous; explain how you're preventing their behaviour from bankrupting the service; and outline how they're going to need to behave going forward. If you've not got the authority to make these decisions for them then you shouldn't be messing with the controls.

- Pay a premium for an assurance scheme on top of the MCS such as heat geek etc (if they'll take on a difficult job and or client whilst easy ones are available) - Go for a manufacturer backed umbrella scheme (where a non MCS installer works under e.g. the Viewsmann umbrella and Viessmans design guidance/warrant and MCS certification) but again expect this to only be available with expensive kit and for easy jobs such is demand - Pay somebody you trust what they could be making on another installation (£1k a day next / £2k a day gross for time on site) - Become that professional you can trust and job out the plumbing. - Roll the dice with an Octopus etc and hope they dub out the installation to somebody competent - Wait for more folks to be trained, supply to better match demand, and margins for the above to drop Supply and demand problem. This will not be available for £0.20 in the UK.

Ok. Noise. You're wanting to ask Hitler express permission rather than doing it to the required technical specifications and risking enforcement action for the lack of an appropriate letterhead. That's hardly an *industry* problem. That's a problem with the Hitler department within your local government. Industry would be glad to be rid of such barriers. I've never been bothered myself; but neighbours are decent people and treat planners with similar contempt following previous butted heads. I'm not seeing any realistic enforcement on noise either. If the tech spec complies Hitler would have his little neck wound in by his superiors for going after what's demonstrably a non issue for enforcement.

So what does range need to be? 17 and 23C? I wasn't suggesting fixing the temperature. Just limit the extremes and limit how quickly you can raise it for the 30V crowd or limit how far you can crater it for the 10C crowd. Semi pseudo choice. 80 benefit for 20 restrictions.

Yes it does. Grab the nearest pipe wrangler and tell them where you want the kit siting and the pipes joining. Pay their day rate. Buy the bits. You just don't get the £5k subsidy for buying from a union fitter and having it installed the union way. The REAL PROBLEM you actually have is that demand is through the roof (great) vs the number of pipe wranglers that have trained themselves up. More are training themselves up. The ones you want might not be though as there's no sense in them adding the union costs onto their business/onto each job. Ask your MP to fund an alternative to the MCS "union" just as the idiots subsidised the expansion of the MCS back in the day?

Weather compensate the space heating flow temperature and put locking pins in every TRV to range limit it to 18-22C. Works a treat.

Have you met the archetypal Karen? She knows everything and must be obeyed. Listening is a non-issue for the non-stupid and the under 30s. Karen can't be taught involuntarily though. Karen only learns from Mumsnet and the Daily Mail when Karen can't afford paying the bills associated with being stupid any more. She does the learn; albeit reluctantly. Grandma is easier if you're able to set the controls at 23C and leave them there 24/7/365 on a device that is too small for her to see or for her fingers to touch. IME she also listens more and is more inclined to believe that others know more about this new fangled heating tech that then Karen that's past it / was always a mouth breather but cannot admit as much to herself.

Tado? Most of the apps are better than the IR remotes. Most of the hardwired controls are better too. But yes the £0.20 ones with the £400 A2A units or the £1500 A2A units are naff.

The specs on most units are perfectly fine. It's the installed flow temp in operation vs the theoretical weather compensated flow temp that crushes the real world sCOP. Peak at much over 55C and the run costs become materially worse. Conversely drop to peaking at 45C and there's not much in it dropping to peaking at 35C. There was a very good reason that the Swedes, some 40 years ago back in 1983, decreed that new heating systems should operate at a peak of 55C or below. It's now in UK Part L some 40 years later. You can fit gas if you like but you still have to do all the legwork to make a heating system that'll run at 55C or below to be legal. Head here and you'll find a bunch of systems that, in spite of operating at least peak temps, fall to achieve the theoretical weather compensated sCOP: https://heatpumpmonitor.org/ Heating system design and control shortcomings are the cause; not the heat pumps. Apply the same "MCS accredited garbage" installation quality to high temp systems and you'll have sCOPs around the 2 mark for twice the operating costs as a system with a sCOP of 3.5 (once you factor in the no gas standing charge saving) - which over 10-20 years quickly pays for some upgrades to make it work at a lower temp hence it not being popular

So...you proved that it'll work just fine with a heat pump running and 50 degC...even if you were to switch the thing off for 8 hours a day? Why do conclude that 70 degC is required? (even on this sample of one) UFH isn't required for adequate (sCOP 3.5+) enough results to make the installation worthwhile. (from a carbon and marginal operating cost perspective) Agree that turning most houses into rubble upon which to erect a new timber framed or lightweight block constructed house would be ideal. In the interim...

Why those figures? It really isn't needed in the vast majority of houses. The gas boys and girls would like the market to think that this is the mass market but actually no, the *mass* market really is about 55C